The present invention relates to compositions for personal care products. More particularly, the present invention relates to silicone compositions which achieve conditioning benefits in hair care products.
Silicones are widely used in hair care products due to the conditioning benefit that they impart to hair. By modem day technology, the silicone is deposited on hair during the application process but is held only by weak physical forces, such as hydrogen bonding or van der Waals interactions. Because the interactive forces are weak, the benefits of silicone by deposition are short lived. Generally, conditioning benefits are attributed to the deposition of high molecular weight, high viscosity fluids and gums which can weigh down the hair. Buildup of silicone compositions is an issue in hair care, and it is perceived by consumers to be a serious negative. Beneficial conditioning effects can also be caused by treating hair with silanol capped amino-functionalized silicones. These can undergo condensation cure reactions on hair to form somewhat durable films. Buildup is still a concern upon repeated applications.
It is widely known by those skilled in the art that covalent bonding is one key to xe2x80x9cpermanentxe2x80x9d hair treatment. Processes which alter the structure of the hair, such as permanent wave and color treatment methods, do provide longer lasting effects. These processes include glycolate reduction and peroxide reoxidation. A significant disadvantage of these processes is that they are very damaging to hair and can only be carried out infrequently.
Gough et al. in U.S. Pat. Nos. 5,523,080 and 5,525,332 describe the synthesis of silicone-azlactone polymers which exhibit covalent bonding and xe2x80x9cpermanentxe2x80x9d conditioning benefit. Gough et al. discuss incorporating an azlactone-functionalized copolymer which consists of vinylazlactone and methacryloyl polydimethylsiloxane monomers into a silicone-active group-hair structure. The hair treatment using the silicone-azlactone polymers does not consist of the steps of reduction with a glycolate or reoxidation with peroxide.
It is desirable to produce silicone compositions which can be used to treat damaged hair and provide durable benefits. Thus, silicone products are constantly being sought which can both covalently bond to hair as well as impart hair care benefits appreciated by consumers.
The present invention provides a silicone composition which comprises at least one polysiloxane or silicone resin containing at least one linker, and either one or two molecular hooks.
The present invention further provides a method for making a silicone composition comprising at least one polysiloxane or silicone resin, at least one linker, and in a range between one and two molecular hooks, which method comprises combining a linker with a molecular hook and a polysiloxane or silicone resin.
The present invention includes a silicone composition which includes at least one polysiloxane or silicone resin containing at least one linker, and either one or two molecular hooks. When the molecular hooks are present in a range between 1 and 2, there is significantly less buildup than when hair is treated repeatedly with formulations containing greater than two molecular hooks. xe2x80x9cSignificantly less buildupxe2x80x9d as used herein refers to a measurably lesser amount of silicone deposited on hair as a result of repeat applications, as determined by x-ray fluorescence, when the silicone composition comprises between 1 and 2 molecular hooks versus greater than 2 molecular hooks.
The linker is bound to both a molecular hook and to an atom of a polysiloxane or silicone resin. Preferably the linker is bound to a polysiloxane or silicone resin through a silicon (Si), carbon (C), oxygen (O), nitrogen (N), or sulfur (S) atom, and most preferably through a silicon atom. When more than one linker is present, it is also contemplated that linkers may be bound to a polysiloxane or silicone resin through more than one type of atom, for example through both silicon and carbon atoms.
The present invention includes a silicone composition having the formula:
MaMxe2x80x2bDcDxe2x80x2dTeTxe2x80x2fQg
where the subscripts a, b, c, d, e, f and g are zero or a positive integer, subject to the limitation that the sum of the subscripts b, d and f is one or two; where M has the formula:
R343SiO1/2,
Mxe2x80x2 has the formula:
(Zxe2x88x92Y)R352SiO1/2,
D has the formula:
R362SiO2/2,
Dxe2x80x2 has the formula:
(Zxe2x88x92Y)R37SiO2/2,
T has the formula:
R38SiO3/2,
Txe2x80x2 has the formula:
xe2x80x83(Zxe2x88x92Y)SiO3/2,
and Q has the formula SiO4/2, where each R34, R35, R36, R37, R38 is independently at each occurrence a hydrogen atom, C1-22 alkyl, C1-22 alkoxy, C2-22 alkenyl, C6-14 aryl, C6-22 alkyl-substituted aryl, or C6-22 aralkyl which groups may be halogenated, for example, fluorinated to contain fluorocarbons such as C1-22 fluoroalkyl, or may contain amino groups to form aminoalkyls, for example aminopropyl or aminoethylaminopropyl, or may contain polyether units of the formula (CH2CHR40O)k where R40 is CH3 or H and xe2x80x9ckxe2x80x9d is in a range between about 4 and about 20; Z, independently at each occurrence, represents a molecular hook; and Y, independently at each occurrence, represents a linker. The term xe2x80x9calkylxe2x80x9d as used in various embodiments of the present invention is intended to designate both normal alkyl, branched alkyl, aralkyl, and cycloalkyl radicals. Normal and branched alkyl radicals are preferably those containing in a range between about 1 and about 12 carbon atoms, and include as illustrative non-limiting examples methyl, ethyl, propyl, isopropyl, butyl, tertiary-butyl, pentyl, neopentyl, and hexyl. Cycloalkyl radicals represented are preferably those containing in a range between about 4 and about 12 ring carbon atoms. Some illustrative non-limiting examples of these cycloalkyl radicals include cyclobutyl, cyclopentyl, cyclohexyl, methylcyclohexyl, and cycloheptyl. Preferred aralkyl radicals are those containing in a range between about 7 and about 14 carbon atoms; these include, but are not limited to, benzyl, phenylbutyl, phenylpropyl, and phenylethyl. Aryl radicals used in the various embodiments of the present invention are preferably those containing in a range between about 6 and about 14 ring carbon atoms. Some illustrative non-limiting examples of these aryl radicals include phenyl, biphenyl, and naphthyl. An illustrative non-limiting example of a halogenated moiety suitable is trifluoropropyl.
The polysiloxanes or silicone resins of the present invention are typically prepared by the hydrosilylation of an organohydrogen silicone having the formula:
MaMHbDcDHdTeTHfQg
where the subscripts a, b, c, d, e, f and g are zero or a positive integer, subject to the limitation that the sum of the subscripts b, d and f is one or greater; M, D, T and Q are defined as above;
MH has the formula:
R353xe2x88x92hHhSiO1/2,
DH has the formula:
H2xe2x88x92iR37iSiO2/2,
TH has the formula:
HSiO3/2,
where each R35 and R37 is independently as defined above; subscript h is in a range between 1 and 3; and subscript i is 0 or 1.
Hydrosilylation is typically accomplished in the presence of a suitable hydrosilylation catalyst. The catalysts preferred for use with these compositions are described in U.S. Pat. Nos. 3,715,334; 3,775,452; and 3,814,730 to Karstedt. Additional background concerning the art may be found at J. L. Spier, xe2x80x9cHomogeneous Catalysis of Hydrosilation by Transition Metals, in Advances in Organometallic Chemistry, volume 17, pages 407 through 447, F. G. A. Stone and R. West editors, published by the Academic Press (New York, 1979). A preferred catalyst contains platinum. Persons skilled in the art can easily determine an effective amount of platinum catalyst. Generally, an effective amount is in a range between about 0.1 parts per million and about 50 parts per million of the total silicone composition.
The organohydrogen silicone compounds that are the precursors to the compounds of the present invention may be prepared by the process disclosed in U.S. Pat. No. 5,420,221. The ""221 patent discloses the redistribution of polydimethylsiloxane polymers with organohydrogen silicone polymers and optionally, added chain stopper, to provide a silicone with randomly-distributed hydride groups using a Lewis acid catalyst, preferably a phosphonitrilic compound.
Synthesis of the polysiloxane or silicone resin may also be performed by other methods known to those skilled in the art, for example, the hydrosilylation of a monomer such as methyldichlorosilane could be followed by co-hydrolysis with the appropriate dialkyldichlorosilane and optionally, chlorotrimethylsilane.
It is to be noted that as pure compounds, the subscripts describing the organohydrogen siloxane precursor and the hydrosilylation adduct of the present invention are integers as required by the rules of chemical stoichiometry. The subscripts will assume non-integral values for mixtures of compounds that are described by these formulas. The restrictions on the subscripts heretofore described for the stoichiometric subscripts of these compounds are for the pure compounds, not the mixtures.
In specific embodiments of the present invention, the silicone composition typically comprises at least one compound of the following formulas, (I), (II), (III), (IV), (V), or (VI): xe2x80x83(R323SiO1/2)a[(Zxe2x88x92Y)R332SiO1/2]b(SiO4/2)gxe2x80x83xe2x80x83(VI)
where each R1, R2, R3, R4, R5, R6, R7, R8, R9, R10, R11, R12, R13, R14, R15, R16, R17, R18, R19, R20, R21, R22, R23, R24, R25, R26, R27, R28, R29, R30, R31, R32, and R33 is independently at each occurrence a hydrogen atom, C1-22 alkyl, C1-22 alkoxy, C2-22 alkenyl, C6-14 aryl, C6-22 alkyl-substituted aryl, or C6-22 aralkyl which groups may be halogenated, for example, fluorinated to contain fluorocarbons, may contain amino groups to form aminoalkyls, or may contain polyether units; Z, Z1-3, and Z7-10, independently at each occurrence, represents a molecular hook; and Y, Y1-3 and, and Y7-10, independently at each occurrence, represents a linker; wherein xe2x80x9cmxe2x80x9d in each formula has a value in a range between about 0 and about 26,000, preferably about 0 and about 1000, more preferably between about 1 and about 250, still more preferably between about 3 and about 250, even more preferably between about 5 and about 150, and most preferably between about 15 and about 120; xe2x80x9cnxe2x80x9d in each formula has a value in a range between about 0 and about 2 with the proviso that in formula (II) xe2x80x9cnxe2x80x9d is not 0; xe2x80x9cm+nxe2x80x9d in each formula has a value in a range between about 1 and about 26,000, preferably in a range between about 3 and about 250, more preferably between about 5 to about 150, and most preferably between about 15 and about 120; xe2x80x9cqxe2x80x9d has a value of 1 or 2; xe2x80x9cp+qxe2x80x9d has a value of at least 3, preferably in a range between about 3 and about 20, more preferably in a range between about 3 and about 10, and most preferably in a range between about 3 and 6; xe2x80x9caxe2x80x9d has a value greater than or equal to one; and xe2x80x9cbxe2x80x9d and xe2x80x9cgxe2x80x9d have a value of at least one. R1-33 is preferably methyl. The preferred silicone composition includes a compound of the formula (I) or (II). The polysiloxane or silicone resin typically has a molecular weight in a range between about 100 and about 2,000,000, preferably in a range between about 250 and about 50,000, more preferably in a range between about 500 and about 25,000, and most preferably in a range between about 500 and about 15,000.
In one embodiment of the present invention a polysiloxane- or silicone resin-containing composition includes a preponderance of a specific linear, branched, cross-linked, or cyclic polysiloxane or silicone resin. In other embodiments of the present invention, a polysiloxane- or silicone resin-containing composition comprises a mixture of polysiloxanes, mixture of silicone resins, or mixtures of polysiloxanes and silicone resins which may include linear, branched, cross-linked, and cyclic species. Also, suitable compositions may comprise one or more polysiloxanes, silicone resins, and mixtures thereof which may contain adventitious amounts of other species, for example, arising during the synthesis process for said polysiloxanes or silicone resins, for example at a level in a range between about 0.0001 wt. % and about 5 wt. % based on total silicon-containing species. In illustrative examples, suitable compositions may contain adventitious amounts of D4, or species containing Sixe2x80x94H, Sixe2x80x94OH, Sixe2x80x94Oxe2x80x94 alkyl bonds, and mixtures thereof.
The molecular hook may be selected from the range consisting of heterocyclic molecular hooks, sp2 aliphatic trigonal carbon molecular hooks, sp3 carbon molecular hooks, metal based molecular hooks, non-metal and metalloid based molecular hooks, energy-sensitive molecular hooks and mixtures thereof. The molecular hook is preferably selected from the range consisting of heterocyclic molecular hooks, sp2 aliphatic trigonal carbon molecular hooks, sp3 carbon molecular hooks and non-metal molecular hooks. The molecular hook is more preferably selected from heterocyclic molecular hooks, sp2 aliphatic trigonal carbon molecular hooks and non-metal molecular hooks.
The molecular hook of the present invention preferably comprises a sulfur-containing compound wherein the sulfur-containing protective group may be a heterocyclic ring or ring system. Heterocyclic groups that are suitable for use in the present invention include mono- or polyunsaturated or saturated heterocyclic rings, heterocyclic ring systems, fused heterocyclic ring systems, substituted heterocyclic rings, substituted heterocyclic ring systems or substituted fused heterocyclic ring systems. The heterocyclic rings contain in a range between about three and about thirty members, and may contain electronegative heteroatoms including N, O, S, or P. The heterocyclic rings or ring systems also may contain exocyclic double bonds of the Cxe2x95x90M type wherein M is O, S, NE1 or CE1E2. E1 and E2 used here, and E, E3, and E4 used hereinafter, each represent, independently from one another, a monovalent group which can be a silicone group, H or any of the following: a straight, branched or mono- or polycyclic aliphatic, mono or polyunsaturated alkyl, aryl, heteroalkyl, heteroaliphatic or heteroolefinic system including carbon atoms in a range between about 1 and about 30 together with heteroatoms in a range between about 0 and about 15, especially O, N, S, P, Si, and can incorporate one or more substituents including, but not limited to, mono, poly or perfluoro substitution.
In particular, the molecular hook may be a heterocyclic pyridinium compound (VII), a heterocyclic triazinium compound (VIII), a heterocyclic pyrimidinium compound (IX), or a heterocyclic pyrazine compound (X): 
wherein W represents optional substituents on the heterocyclic ring or ring system, Y represents the linker, Qxe2x88x92 represents a counterion, and E is defined above. The preferred molecular hook is the pyrimidinium molecular hook of formula (IX).
Optional substituents, W, which can be present on the heterocyclic ring or ring system can be selected from electron withdrawing, electron neutral, or electron donating groups with Hammett sigma para values between xe2x88x921.0 and +1.5 comprising carbon-linked groups of the classes defined as E1, E2, E3, and E4; S-linked groups including SE1, SCN, SO2E1, SO3E1, SSE1, SOE1, SO2NE1E2, SNE1E2, S(NE1)E2, SE1(NE2), SONE1E2; O-linked groups including OE1, OCN, ONE1E2; N-linked groups including NE1E2, NE1E2E3+, NE1OE2, NE1SE2, NCO, NCS, NO2, Nxe2x95x90NE1, Nxe2x95x90NOE1, NE1CN, Nxe2x95x90Cxe2x95x90NE1, NE1NE2E3, NE1NE2NE3E4, NE1Nxe2x95x90NE2; other miscellaneous groups including CONE12, CONE1COE2, C(xe2x95x90NE1)NE1E2, CHO, CHS, CN, NC, Hal, and derived groups that connect one or more of the optional substituents via a ring system; Hal is fluorine, chlorine, bromine, or iodine. E, E1, E2, E3, and E4 are defined above. The substituent E is preferably methyl.
The counterion, Qxe2x88x92, can include halides, borates, phosphates, tosylates, mesylates, triflates, and other counterions known to those skilled in the art.
The linker comprises any C1-C100 alkyl, aryl, or alkylaryl group where the C1-100 group can be interrupted by or substituted with aromatic groups or aromatic-containing groups. The C1-100 group may also contain one or more heteroatoms such as O, N, or S. Furthermore, the C1-100 group may be unsubstituted or substituted with heteroatoms such as halogen. Typically, the linker has the formulas (XI) through (XVII) 
where
r is in a range between about 1 and about 10, preferably 2 or 3;
s is in a range between about 0 and about 100, preferably 4 to 20;
t is in a range between about 0 and about 100, preferably in a range between about 0 and about 20, and most preferably 0;
u is in a range between about 1 and about 10, preferably 1;
v is in a range between about 1 and about 10, preferably 2 or 3;
w is 1 or 2;
x is 1 or 2;
X is O, NOH, NOR or NR, preferably O;
wherein R is independently at each occurrence hydrogen (H), C1-22 alkyl, C1-22 alkoxy, C2-22 alkenyl, C6-14 aryl, C6-22 alkyl-substituted aryl, or C6-22 aralkyl where the can be unsubstituted or substituted with heteroatoms such as oxygen (O), nitrogen (N), sulfur (S) or halogen;
wherein R39 is independently at each occurrence hydrogen (H), C1-22 alkyl, C1-22 alkoxy, C2-22 alkenyl, C6-14 aryl, C6-22 alkyl-substituted aryl, C6-22 aralkyl, or fused ring system which may or may not be fused to the phenyl group where the C can be unsubstituted or substituted with heteroatoms such as O, N, S or halogen. R39 is preferably H. If R39 represents an aryl group, it can be fused to the ring in Formulas (XIII) through (XVI);
A is O, NOH, NOR, NR or S, preferably O;
B is O, NOH, NOR, NR or S, preferably O or NR and most preferably O;
and where the polysiloxane or the silicone resin is bound to the (CR2)r (Formula XI, XII, XIV, and XV), (CR2)v (Formula XIII and XVI), or (CR2)w (Formula XVII). Any of the linker structures shown in Formulas (XI) through (XVII) can also be interupted with cycloaliphatic rings or aromatic rings. Substituents on the phenyl group of formulas (XIV), (XV), (XVI), and (XVII) may be present at any free valence site. The polysiloxane or silicone resin may or may not contain other functionalities by substitution at silicon atoms either the same as or distinct from those bound to the linking groups described above, such as amine-, polyether-, alkyl-, or heteroalkyl-containing groups.
The linker is typically derived from a polysiloxane or silicone resin bound linker precursor which comprises a linker bound to a leaving group. Illustrative leaving groups include halides such as chloride, bromide and iodide; tosylate, mesylate, phosphate; cyclic leaving groups (that is, those in which the leaving group remains bound in the linker) such as epoxy or other cyclic leaving group containing at least one heteroatom; and other leaving groups known to those skilled in the art. Preferred leaving groups are bromide, chloride, and iodide. In synthesis, the leaving group is replaced by a molecular hook, so that the linker becomes bound to a molecular hook.
The method for making the silicone compositions of the present invention includes combining a molecular hook, a polysiloxane or silicone resin, and a linker . The sequence of addition can be varied, for example, the linker and the molecular hook can be combined and this combination can be sequentially combined with a polysiloxane or a silicone resin. Preferably, the linker is combined with a polysiloxane or silicone resin and the combination is sequentially combined with the molecular hook.
Silicone compositions of the present invention which include at least one polysiloxane or silicone resin containing at least one linker, and at least one molecular hook typically impart cosmetic and other durable benefits in products such as hair care products, but also including, textile care products, cosmetic products, oral care products, and animal care products. A particular advantage of the present invention is that many of the described linkers provide solubility, in consumer relevant media, to the silicone composition as well as the potential for additional hair care benefits which may or may not be typically associated with the functional groups of the linker.
The silicone compositions can be delivered to a substrate, for example hair, in any appropriate formulation, for example water or water and alcohol mixtures which can contain in a range between about 1% by weight and about 99% by weight alcohol based on the total formulation.